The present invention relates to a camera having a zooming function.
Hitherto, as an example of an 8 mm camera with a power zoom, there are those constructions shown in FIGS. 1a and 1b. In FIGS. 1a and 1b, numeral 1 is a camera body, in front of this body 1 is provided a photo lens 2 and in the rear thereof is provided a finder ocular portion 3. This camera body 1 is provided with a grip 4 gripped by hand when photographing, and near this grip 4 is provided a photo-operation button 5 operated by the hand which holds the grip 4. This photo-operation button 5, as shown in FIG. 2, is movable in a chassis 6 against a spring 7 in said body 1 whereby, a part of the button 5 closes a contact 8 which energizes a photo-motor 10 by means of a D.C. supply source 9 through this contact 8. On the upper portion of one side surface of the body 1 is provided a zoom operation button 11 which controls an electric power zoom function. This operation button 11 may be a two directional button which can switch zoom-up to zoom down and vice versa.
In using such a camera, therefore, the grip 4 is usually gripped by the right hand and the photo-operation button 5 is operated, by a finger of the right hand, while the upper part of the camera body 1 is held by the left hand and a zooming photograph, that is, the zoom-up or zoom-down is taken by operating the zoom operation button 11 with a finger of the left hand.
In such a camera, however, the operation by both hands is a general rule, so that if only a single hand is available to be used, a photograph can be taken but a valuable zoom effect cannot be used and it is very inconvenient. Even if both hands can be used, when a zoom effect is suddenly required in photographing, the zoom operation button 11 has to be found by the left hand, and this is also inconvenient in handling. Also in such a camera, a photo operation button 5 and a zoom operation button 11 are separately provided and each of them are independently operated, so that if the zooming operation is carelessly made while not actually photographing, battery power is unnecessarily consumed.
In order to eliminate such disadvantages, a lock function has been provided in each operation button 5, 11, or alternatively a lock function is provided in the photo operation button 5 only, with provision of an ON-OFF switch in a zoom motor circuit responsive to the zoom operation button 11 interlocked with the operation button 5. With this arrangement, however, the operation becomes troublesome and a number of parts are increased and reliability is deteriorated. Further, such a camera only switches zoom-up or zoom down by means of a zoom operation button and cannot control a zooming speed continuously.
Recently, there has been invented a mechanism such that a switch 82 for switching a speed of the zooming motor from a high speed to a low speed is provided together with the zoom operation button 11 as shown in FIG. 12a, but this is not suitable for switching operation during the zooming photographing with the use of both hands as described above, and as a result almost no photographing speed change effect can be expected.